Promethium

61
Pm
Gruppe
n/a
Periode
6
Block
f
Protonen
Elektronen
Neutronen
61
61
84
Generelle Eigenschaften
Ordnungszahl
61
Atommasse
[145]
Massenzahl
145
Kategorie
Lanthanoide
Farbe
Silber
Radioaktiv
Ja
Named after the Greek Prometheus, who, according to mythology, stole fire from heaven
Kristallstruktur
n/a
Geschichte
The existence of an element between neodymium and samarium was first predicted by Czech chemist Bohuslav Brauner in 1902.

Promethium was first produced and characterized at Oak Ridge National Laboratory in 1945 by Jacob A. Marinsky, Lawrence E. Glendenin and Charles D. Coryell.

It was produced by the separation and analysis of the fission products of uranium fuel irradiated in a graphite reactor.
Elektronen pro Schale
2, 8, 18, 23, 8, 2
Elektronenkonfiguration
[Xe] 4f5 6s2
Pm
Promethium is the only lanthanide that has no stable isotopes
Physikalische Eigenschaften
Aggregatzustand
Fest
Dichte
7,26 g/cm3
Schmelzpunkt
1315,15 K | 1042 °C | 1907,6 °F
Siedepunkt
3273,15 K | 3000 °C | 5432 °F
Schmelzwärme
7,7 kJ/mol
Verdampfungswärme
290 kJ/mol
Spezifische Wärmekapazität
-
Häufigkeit in der Erdkruste
n/a
Häufigkeit im Universum
n/a
Pitchblende,
Danksagungen für Bilder: Wikimedia Commons (Geomartin)
Pitchblende, a uranium ore and the host for most of Earth's promethium
CAS-Nummer
7440-12-2
PubChem CID Number
n/a
Atomeigenschaften
Atomradius
183 pm
Kovalenter Radius
199 pm
Elektronegativität
-
Ionisierungsenergie
5,582 eV
Molares Volumen
22,39 cm3/mol
Wärmeleitfähigkeit
0,179 W/cm·K
Oxidationszustände
3
Anwendung
Promethium is also used in atomic batteries for spacecraft and guided missiles.

Promethium is also used to measure the thickness of materials by evaluating the amount of radiation from a promethium source that passes through the sample.

It has possible future uses in portable X-ray sources, and as auxiliary heat or power sources for space probes and satellites.
Promethium is harmful due to its radioactivity
Isotope
Stabile Isotope
-
Instabile Isotope
126Pm, 127Pm, 128Pm, 129Pm, 130Pm, 131Pm, 132Pm, 133Pm, 134Pm, 135Pm, 136Pm, 137Pm, 138Pm, 139Pm, 140Pm, 141Pm, 142Pm, 143Pm, 144Pm, 145Pm, 146Pm, 147Pm, 148Pm, 149Pm, 150Pm, 151Pm, 152Pm, 153Pm, 154Pm, 155Pm, 156Pm, 157Pm, 158Pm, 159Pm, 160Pm, 161Pm, 162Pm, 163Pm